The present invention relates to a projectile suitable for delivering a quantity of pressurized material, and particularly, to an aerosol grenade which is adapted to be launched, from a gun or similar device, and which does not begin releasing the pressurized material until impact of the projectile.
Some gaseous materials must be released at a location away from the party who wants to release them for effective use of these materials and for protection of the party releasing them. For example, law enforcement personnel may use tear gas or similar disabling agents to control crowds and to dislodge barricaded persons and those personnel wish to be able to disperse the tear gas over a target area which they are away from. The law enforcement personnel who use such disabling agents should be protected from accidental discharge. Furthermore, it must be assured that a person at whom a tear gas grenade is targeted is not able to capture the still active tear gas grenade and throw it back.
In the prior art, dispersable materials, e.g. tear gas, were dispersed by various techniques. In one technique, the dispersable material was combined with a flammable material. Burning the combined materials vaporized them and they thereafter spread as a smoke cloud. In another technique, the dispersable material is packed with an explosive charge which detonates upon impact and causes the dispersable material to spread over an area.
The major shortcomings of these prior art techniques is that the combustion or explosion associated with each technique poses a fire or concussion hazard to buildings, property and people. A container with slow burning contents can be picked up and thrown back at law enforcement personnel. An exploding projectile can cause injury. If a projectile does not explode upon impact, it poses a danger to innocent bystanders or police personnel who attempt to retrieve it.
U.S. Pat. No. 4,195,572 discloses a projectile which is filled with a dispersable material and which is suitable for launching by a gun. The material is stored in a pressurized can in a housing. The rear or bottom end of the housing, which is the end toward the user, carries a piercing pin. The can is slidably mounted in the housing and is spaced away from the pin. As the projectile is launched, the inertia of the can impacts it against the piercing pin and the bottom of the can is punctured. The later impact of the front of the projectile hitting a target releases the can from the piercing pin and the pressurized contents of the can are discharged through its pierced bottom and pass out through holes in the hollow housing.
In the above described projectile device, the pressurized container is pierced before the projectile reaches its destination, i.e. at launch. This poses the danger that the contained material may be released before impact of the projectile. Further still, the punctured can could explode at launch or disperse material over the person firing the projectile. Furthermore, the device of the 4,195,572 patent, as well as other prior devices, releases the pressurized material slowly, so that the can could be picked up and hurled back at law enforcement personnel.